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Reflector Dip Trends In Seismic Sh-Wave Imaging Of A Modern Lower Mississippi River Point Bar, Adam Gostic

LSU Master's Theses

Various studies of ancient point bars have noted that a relationship can be observed between the dip angle and grain size of point bar lateral accretion deposits, with the most mud-rich deposits tending to exhibit the greatest dip. No analysis and only cursory explanations for this relationship have been provided. Additionally, buried mid-channel bars are absent from typical models of point bar architecture.

We successfully image the architecture of late-stage point bar deposits with a near surface 2D seismic SH-wave reflection survey and generate an SH-wave velocity model of the subsurface in the study area in order to interpret the …

Channel-Levee Complexes And Sediment Flux Of The Upper Indus Fan, Taylor Landry Berlin

LSU Master's Theses

The Indus Fan with a volume of 4.5 million km³ is the second largest submarine fan on Earth, only behind its neighbor to the east The Bengal Fan. It formed off the passive margin of Pakistan-India in the northern Arabian Sea. One of the more important aspects of the Indus Fan is its mostly complete sediment record of what has been eroded from the western Himalayan and Karakoram Mountains which act as the main source for the Indus River system. Since the initiation of the Himalaya about 50 Ma, sedimentation rates have fluctuated. This study attempts to calculate a new …

On The Long Duration Of Till Sheet Construction : A Reassessment Of How Quaternary Grounding Line Translations Relate To Near-Surface Seismic-Stratigraphy Of Eastern Ross Sea, Antarctica, Sydney Grace Bowles

LSU Master's Theses

Previously acquired seismic surveys provide strong evidence that the post-Last Glacial Maximum (LGM) retreat of the West Antarctic Ice Sheet (WAIS) deposited a back-stepping succession of seismically-resolved grounding zone wedges (GZWs) in eastern Ross Sea. However, the chronology of WAIS retreat is debated. The conventional view is that three GZWs (Red, Brown, and Gray Units) were deposited since the LGM. An alternative view, based on recent radiocarbon dates, is that the youngest GZW (the Gray Unit) was deposited during the LGM. If correct, then the older GZWs (Red and Brown Units) were deposited prior to LGM. A recent study (Bart …

Investigation Into The Cause Of Earthen Embankment Instability Along The "V-Line" Artificial Levee In Marrero, Louisiana, Usa, Jason Hicks

LSU Master's Theses

The “V-line” levee, located in Marrero, LA, has a crack along its crest, measuring approximately 100 meters in length, 30 centimeters in depth, and 30 centimeters in width. This crack is a sign of levee instability. Seismic shear wave, CPT, and laboratory shear strength data were collected and processed to identify the cause of the instability. A zone of low seismic shear wave velocity was interpreted approximately 3 meters deep from the berm of the levee. Because of the large spacing between laboratory shear strength test sampling and CPT sites, a similar zone of low shear strength was not found …

Spatial Variations Of Salinity, Temperature And Pressure On The Flank Of A Salt Dome, Offshore Louisiana: Implications For Mechanisms Of Fluid Flow, Andrew Kevin Steen

LSU Master's Theses

Salt dome dissolution in the Gulf of Mexico sedimentary basin is a primary cause for elevated pore water salinities in the subsurface. Temperature, pressure, salinity, lithology and fluid density are parameters often used to identify preferential conduits and driving forces for fluid migration. These parameters were calculated using 20 wireline logs covering 40 km² on the south flank of a salt dome on the continental shelf, offshore Louisiana. 3-D seismic has been utilized to determine location of faults, to aid in sand correlation, and to provide a structural overview of the dome. Vertical and lateral variations in lithology, salinity, temperature, …

Miocene Fluctuations Of The West Antarctic Ice Sheet And The Influence Of Meltwater On The Ross Sea Outer Continental Shelf: Seismic-Stratigraphic Based Interpretations, Sean Francis Kerrin

LSU Master's Theses

The changing extents of the West Antarctic Ice Sheet (WAIS) and the manifestation of meltwater discharge on the outer shelf during the Miocene were deduced using seismic stratigraphy and seismic facies interpretations. Deep Sea Drilling Project (DSDP) Leg 28 drill sites were used for chronologic constraints of the outer continental shelf (OCS) seismic stratigraphy to establish correlations to coeval strata at the inner shelf SMS-ANDRIL drill site. The evidence indicates that grounded ice sheets periodically existed on the OCS during the early and middle Miocene and in section inferred to have been deposited in the late-Miocene. Large-scale grounding events occurred …

Genetic Stratigraphy And Geochronology Of Last Interglacial Shorelines On The Central Coast Of South Carolina, Russell Willis

LSU Master's Theses

This study investigated the shallow subsurface of the Lower Coastal Plain of South Carolina in order to determine the sea-level history and stratigraphic architecture preserved within several emergent shoreline complexes. The absolute age of each shoreline complex was estimated using single-aliquot regenerative-dose (SAR) optically stimulated luminescence (OSL) techniques. The resulting geochronology was incorporated into a high-resolution stratigraphic framework defined by ground penetrating radar calibrated with deep sediment cores, many of which contain a complete sequence of highstand deposition. Three emergent barrier complexes were identified within the Lower Talbot, Pamlico, and Princess Anne terraces, and assigned to sea-level highstands during interglacial …

A Comparison Of A High-Resolution Survey And A Three-Dimensional Seismic Survey In A Feature-Rich Region Of The Green Canyon Area, Gulf Of Mexico, Bruce Miles Samuel

LSU Master's Theses

Recent advances in Autonomous Underwater Vehicle (AUV) technology have revolutionized the positioning and accuracy of high-resolution deep sea mapping tools. Geologic hazard and engineering surveys by AUV’s are producing high-resolution data sets of a quality that has never before been seen. Three-dimensional (3D) seismic data, though traditionally used for only deep subsurface mapping of large areas, is now being reprocessed at a higher resolution and utilized in well site investigations and geologic hazard assessments. This study makes a comparison between a 3D seismic survey and an AUV high-resolution survey in order to determine the strengths and weaknesses of both of …